A Safety and Antitumor Activity Trial of Immunoradiotherapy Combinations as a Treatment Option for Subjects With Metastatic Solid Tumors

A Phase 1 Dose Finding and Phase 2, Randomized, Open-Label Trial to Evaluate the Safety and Clinical Activity of Immunoradiotherapy Combinations as a Treatment Option in Subjects With Metastatic Solid Tumors

The main purpose is to assess the safety and clinical activity of GEN1042 in combination with radiotherapy or GEN1042 in combination with radiotherapy and pembrolizumab as a treatment option for participants with metastatic solid tumors.

The study will be conducted in two parts: Part 1 (dose-finding) and Part 2 (randomization).

Part 1 will evaluate the safety of immunoradiotherapy combinations and establish the dose(s) to be evaluated in Part 2.

Part 2 will evaluate the anti-tumor activity of immunoradiotherapy combinations at the established dose(s) from Part 1.

Participants in both parts are treated with one of the following combinations:

• Radiotherapy + GEN1042
• Radiotherapy + GEN1042 + Pembrolizumab

While participants in Part 1 are assigned sequentially (GEN1042 without pembrolizumab is investigated first), participants in Part 2 are randomized 1:1 in the two treatment arms.

Key Inclusion Criteria:

• Participants with histologically confirmed non-central nervous system (CNS) solid tumor that is metastatic and for whom there is no available standard therapy.
• At least 18 years of age.
• Signed informed consent prior to any screening procedures.
• Measurable disease according to RECIST v1.1.
• Life expectancy of >3 months.
• Qualify for palliative radiotherapy as an available option for disease management.
• Eastern Cooperative Oncology Group (ECOG) 0-1.
• Normal or adequate liver, renal, cardiac and bone marrow function.

Key Exclusion Criteria:

• Prior malignancy except for non-melanoma skin cancers and in situ cancers.
• Condition contraindicating radiotherapy.
• Rapidly progressing disease.
• Active, known or suspected autoimmune disease.
• History of non-infectious pneumonitis that required steroids or currently has pneumonitis.
• Contraindications to the use of pembrolizumab.
• Condition requiring systemic treatment with either corticosteroids or other immunosuppressive medications within 14 days of first treatment.
• Received an allogeneic tissue/solid organ transplant.
• Active infection requiring systemic therapy.

Note: Other protocol defined inclusion and exclusion criteria may apply.